Air cleaner



w. w. Lowrfi v 21,006,927 V July-2', 1.935.

, AIR CLEANER Filed Dec. 17, 19:54

' llvvzlvlroz' Wilfred W Lowfher fir; Hm ATTOP/VE YJ llatented July 2, 1935 v: a v

- mmmm PATENT- omcB AIR CLEANER Wilfred W. 'Lo'wther, Minneapolis, Minn., as- 's'ignor tit Donaldson Company, Inc., St. Paul, I Minn, a corporation of Minnesota Application December 17, 1934, SerlalNo. 757,828

. T ZClaima. (01183-45) My present inventionrelatesto air'cleanersand; 1y opposite to'said outlet passage. Also it'will Y a is in the nature of an improvement 01101; modi- *be noted by reference particularly to Fig. 2- that cation or the air cleaners disclosed and cla'imed'in the outer portion or rim of the bailie II is widest my pending applications; S. N. 702,482, and 702,- adjacent to the'outlet'port l2 and is narrowest ,5 483, filed or dateDeceinber 15, 1933 which have at a point diametricallyopposite to said outlet it now matured into Patents No. 2,000,706, granted passage. Otherwise stated, the eccentric air pa's- May '7, 1935, and No. 1,991,758, granted Feb. '19, sage l3v progressively increases, and the outer rim 1935, respectively. This invention relates particof vthebaille Ii progressivelydecreases in width Y ularlyfto an improved relative 'arrangement of; in both directions circumferentially from said casing, air intake and outlet conduits and interoutlet port l2. The-importance of this structure 10' I 'mediate air passages, wherebyjthe flow of air will be later considered. Withinand secured to 9 through the filtering chamber is equalized and the bottom of the oil well i is an oil-cup l4 that made. substantially even throughout the crossis of much less diameter than the oil well, 0f 11- sectional-area-thereof. siderably greater diameter than the lower endof Generally stated, the invention consists of the the intake tube4' and the upper end of which is m;'

novel devices, combinations ofdevices and arconsiderably above-the planeof the lower edge of a eme of pa shereinatter described and dc the'airtube. I v fined in the claims; Within the casing surrounding the air intake In the accompanying drawing, which illustrates tube is an annular screen pre bly made lip-0f.

the invention, like characters indicate like parts woven .wire screen elements. These screen ele- 20 throughout the several views. ments I! may take various forms, but as shown, Referring to the drawing: are of a type and arrangement disclosed and Fig. 1 is a view partlyin side elevation and partclaimed inthe application of Frank A. Donaldson ly in vertical axial section, showing an air cleanentitled Air cleaner, filed of even date herewith.

5. er involving my invention; and An expanded air intake chamber I! is-formed Fig. 2 is a horizontal section taken on the line at the upp n 0 t intake tube 4 y he 22 of Fig. 1. annular battle it and by an upper baiile plate I] The air cleaner shown involves an outer casing which, atits edge is secured to the top of the or shell that is preferably in the form of-an upcasing. This bailie I] is provided with circumright cylinder 3, the lower end of which is priferentially spaced-air intake ports it which con- '30 marily open. An axial air intake tube 4 extends stitute no part of my present invention, but are downward through the casing 2. A large or main preferably of the arrangement disclosed and I 011 well I of cup-shaped form is telescoped onto claimed in the pending application of Frank A. y the lower end of the casing 3 and closes the lower, Donaldson, S. N. 722,458, filed of date April 28,

end of the latter. I x 1934 which has now matured into Patent No. as

To securely but detachahly hold the'well tele- 1,992,025, granted Feb. 19, 1935. A scoped onto the casing, as stated. nut-equipped O diam bolts 9 are passed through lugs I and through the per ends of a bar 8 that is applied to the bottom of The Oil W l and 111' wi be Primarily fill d 40 .the OH well. At the upper end of the casing is app o i to t e lev i the top-0i the cup to an air outlet chamber 9 that is formed between 20, t when the engine is in action, M annular baiile plates II and H. The upper baf-' vacuum will be produced in the air chamber I he plate 10 is secured to the upper end of the and this, of course, will draw air downward air inlet tube 4 and to the upper end of the casthrough the air intake tube 4 and through ins. The lower baiile plate II is secured to the the oil in the cup. By the inrush of air, the 45 air tube 4 and to the casing! at a point consul oil will be displaced and carried upward through erably belowalateralair outlet e it, which the annular space. between the lower end of latter is adapted and intended to be connected .the air tube and the rim of the cup, and from to the carburetor of an internal c0l1lbll8tl0n..!ithence will be carried upward through the screen so gine. As an important feature, the lower name I elements. The extent to which the air will carry which constitutes the bottom of'the air outlet the oil upward through the screen elements will,

v chamber 0 is formed with an eccentric annular of course, depend largely upon the speed of the air passage it, the narrowest portion of which is engine and the velocity of the air. Before the 5 nearest to the lateral outlet passage i2 andthe oil reaches the uppermost screen element, how- 56 widest portion of whichisatapoint diametricalever, it will be released from the air current and will flow back over and through the screens. In running down onto and through the screens, the oil will form films over the openings in the screen through which the air must pass so that all the dust carried'by the air will be taken from the air and returned with the oil downward and back to the oil well.

Inasmuch as thelateral air outlet passage i2 is eccentric to the axis of the air outlet chamber l, the highest -vacuum will be produced on that side immediately adjacent to the said outlet. With an eccentric airpassage in the baiile forming the bottom of the air chamber I, there will be a tendency for' the air to drift to that side on which the outlet is located and this would produce an uneven flow of oil and air upward through the screens. This tendency of the air draft to drift as stated is overcome and neutralized by the above described eccentric arrangement of the air passagein said botto'rng-forming ballie, and as hasbeen demonstrated in practice, an even flow of air and oil through'the screen at all circumferential points thereof can be ac complished. In practice, this novel arrangement of the intermediate air passage, to wit: the pas-.

sage in the bame H in respect to the lateral or eocentrically located air outlet has been found to increase the air capacity and cleaning eiiiciency of the air cleaner and hence to be of. very great importance.. From what has been said, it will be understood that the air cleaner illustrated in the drawing is capable of modiset of said air outlet.

let is in the form of wire screens, but the said dust-intercepting means may, of course, take various forms so far as the present invention is concerned. By oifsetting the e in the baffile which is located between the dust and oilintercepting means and the air outlet in a direction opposite to the direction in which the air outlet is offset from the axis of the casing,

theeven flow of air through'the screens and ofoil through certain of the screens, is insured.

What I claim is:

1. In an air cleaner, the combination with a casing having an oil well at its bottom and an axial air inlet tube leading to saidoil well, of a screen within said casing surrounding said air intake tube above said oil well, said casing, at a point above the screen being formed with an annular air outlet chamber with an air outlet passage at one side thereof, the bottom of said air outlet chamber being formed by an annular bafiie located above said screen and provided with an eccentric annular air passage, the radial dimension of which is narrowest immediately adjacent said outlet passage and is widest at the diametrioal opposite point, the intake end of said air intake tube .being extended upward through said air outlet chamber.

2. In 'an air cleaner, a casing having an air inlet'and an'airoutlet that is offset from the axis or. the 'casmg and between said inlet and 'outlet an intermediate dust-intercepting means,

and a baille between the latter and said air outlet, said baflle forming an air passage that is eccentrically offset from the axis of the casing in a direction opposite from the direction of oil- WILFRED 

